PN Racing 4D Trigger -- Setting it Up

Sorry it took me so long to get this article out, but it is here finally.

The PN Racing 4D Trigger is a pretty clever bit, essentially it puts all the contact surfaces (forward/reverse) of the trigger on relocatable pivots so you can very carefully control how the trigger feels in your index finger. This allows you to have a true no-play, no-lag trigger, and you can have full confidence in modulating the brake and throttle input as this trigger (when set up properly) WILL NOT slip off your finger. It also looks like the freakin' Terminator, if that's your thing.

You do have to put in some work to get the functionality out of it though, and if you've been wondering how the heck it should be done, you can take a look at my setup and try it out as a baseline.

First things first, adjustments on this trigger are made by a normal 1.5mm hex wrench, which secures a set screw sitting inside a ball. Overtighten any one of these balls and you will mar the steel shaft, so be warned -- I messed this one up early on and had to Dremel polish the shaft to get the balls back on lol.

As far as adjusting the trigger goes, it's all giong to depend on how your hand is preferably positioned. My left hand tends to sit high/"choke up" on the EX-10 pistol grip, so that's why the first alu piece on your finger pad (let's call this the forward pad, as you press this to go) sits almost at its highest setting for me (teal arrow pointing up). If you grab your radio at a lower position then you will want to lower this part to match where your index finger most naturally lines up.

The second arrow in the above image indicates the slight twist outwards that I give the forward pad, in order to mesh exactly right with the angle of my index finger when in neutral trigger position. It's less than 5 degrees of twist, but this makes all the difference because the edge of the forward pad can be sharp! I actually filed mine down on all edges with a dremel and sandpaper to smooth out the contours.

On to the piece that contacts the back of your finger (let's call this the "reverse pad"). There are many ways to set this one but the most important thing is to avoid scratching your finger at any point during the forward/reverse throttle travel. Again, the edges are sharp so I filed down everything, but even then the curve of the reverse pad is a little too much, and I can't make it fit comfortably on my relatively slender finger. So, that's why the velcro is there. To make it fit with the extra thickness of the velcro, I moved the shaft mounting the reverse pad outwards (arrow pointing left, below), slide the reverse pad itself downwards to match up to where the forward pad would place my finger, and finally gave the reverse pad a bit of a twist too in order to feel the best in the "transition area" between forward and reverse/braking. With the velcro in place, the twisted mounting of both pads allows the trigger to be really snug, but without pinching my finger in any range of movement.

The way I placed the velcro is also important: the top edge of the forward and reverse pads is exceptionally narrow and no amount of Dremeling/filing would dull it off for me, so I went with plan B and just covered up those edges with velcro. However, you can see (left side of the velcro strip) that the contact area with the forward pad is very, very small, and so I ended up supergluing the entire velcro strip in once I had confirmed that everything was comfortable.

So there you go, from this last closeup you should be able to see that the 4D trigger can really take out 100% of the free space between your finger and your trigger -- the hole left in the gap is pretty much the exact cross-section of my index finger lol. Pretty slick. And with the velcro acting as a comfort pad, I've become much more willing to use the brakes than before, as well as much more able to modulate the brakes from 0-50%. It's an expensive part to buy at first but the added comfort and precision have improved my ability to place the car a lot -- even if you don't gain in absolute fast lap times, you definitely should notice more consistency when your finger doesn't shift on the trigger anymore.

Lastly, the trigger evidently fits all EX-1 (Mars, Mars R, UR), EX-1 KIY and EX-10 models from KO Propo without modification. So for now at least, you can buy only one trigger and move it around whenever you decide to upgrade/change radios.